Phonograph pickup device



Oct. 2,1945"; L. BOBB 2,386,089 L PHONOGRAPH PICK-UP DEVICE Filed" March 51, 1944 of its major objects.

Patented Oct. 2, 1945 PHONOGRAPH PICKUP DEVICE Lloyd. J. Bobb, Glenside, Pa., assignor to Philco Radio and Television Corporation, Philadelphia, Pa., a corporation of Delaware Application March 31, 1944, Serial No. 528,905 16 Claims. (crows-100.41),

This invention relates to phonograph pick-ups of the moving coil type intended for use with lateral-cut recordings.

To avoid the, alternative of translating lateral oscillations of the pick-up stylus into axially directed oscillations of the moving coil and, at the same time, to. ensure that the moving coil will cut enough magnetic flux lines to effect a'satisfactory voltage output per turn, it is expedient that the moving coil be of rather considerable diameter; and in order to ensure transmission of mechanical oscillations of all desired frequencies from the stylus to the moving coil without inordinate loss ordistortion it is necessary to employ a rigid, low-mass coil-supporting structure for mechanically coupling the coil with the stylus. But such a structure, if vibrated axially of a the coil, will, unavoidably, displace a considerable volume ofair and thus produce an objectionable amount of so-called needle-talk whlch is noise propagated directly from the pick-up.

Although a lateral-cut recording-is not intenmotion to the pick-up stylus, it does so nevertheless, by virtue. of what is called pinch-efiecttionally designed to impart lengthwise vibratory which is a phenomenon resulting primarily from variations in the .width of the record groove brought about as a consequence of the fact that the recording styluscuts a groove of less depthwise angularity during its excursions laterally of the groove than it does when not moving laterally of the groove; and secondarily as a consequence of the fact that the reproducing stylus rests on the side-walls of the groove rather than on the bottom. In efiect, the groove may. be considered end to a resilient stationary member, preferablya soft rubber block, which permits the stylus to vibrate both laterally and axially with considerable freedom, while at the same time. affording essential mechanical damping. By providing a stylus support which allows the stylus freely to oscillate axially in response to pinch-eifect" conditions, record groove abrasion is substantially alleviated,

as explainedmore fully in my co-pending application, Serial No. 502,003, filed September 11, 1943, now Patent No. 2,379,782, dated July 3, 1945 but, as previously indicated, oscillation of the coilsupport axially of the stylus is objectionable because of the resultant needle-talk, and is a thing which inevitably would occur if the coil-support were fixedly secured to the stylus.

The solution of the problem thus presented consists, fundamentally, according to this invention, in the provision of a close sliding fit between the stylus andan aperture in the apex of the coil-support through which the stylus extends-which close sliding fit allows the stylus to vibrate length- -wise, substantially without any like movement being imparted to the coil-support, while at the same time ailording good mechanical coupling between the stylus and coil-support as respects lat-t eral vibration of the stylus,

If the fit of the stylus in the aforementioned. aperture is such as to preclude lateral lost motion between stylus and coil-support while at the same time leaving the stylus free to vibrate length as having a "hill and dale noise-producing component in additionto its intentionally-produced lateral undulations.

Lengthwise vibratory movements of a pick-up stylus caused by pinch-effect cannotbe avoided by any correction in the design of the pick-up, but the present invention provides a pick-up construction which largely or completely obviates the otherwise resultant needle-talki and such is one According to the preferred mode-of putting this invention into practice the moving coil is carried shaped member made of thin sheet metal, such as aluminum, and suspended for rotational oscillation on resilient pivots. The coil is wound onthe base portion of-the support andissituated in the magnetic field; and,the actuating stylus-extendsaxially through the apex of said coil-support to wise without transmitting such vibrations to the coil-support, a simple circular aperture will answer the purpose. But I have found it to be quite difficult with a circular aperture to limit lateral lost motion to such magnitude as would not result in objectionable attenuation of the higher audible frequencies while yet making certain that frictional coupling between stylus and coil-support would not-give rise to inordinate vibration of the-coil-support lengthwise of the stylus-which,

, as previously explained, results in needle-talk.

While endeavoring to meet that situation in a practical way, I discovered at length, aftercon-. siderable experimentation, that by making the aperture .of triangular or similar configuration by a cup-like supportcomprising a generally coneand of suitable angularity and appropriate orientation with respect to the locus of the record groove; as explained hereinafter, it is possible to achieve a permanent close running'fit which nullifies lateral lost motion while ensuring continued free longitudinal movement of-the stylus without.

undue frictional drag. This feature of my invention results in suppression of needle-talk to a the exterior thereof and is anchored at its interior gratifying degree without introducing any per- 2 ceptible lossoffidelity while, at the same time,

avoidinga large part of the record abrasion'which would result from pinch-effect if the stylus were not so supported as to be quite yieldable lengthwise.

Due to high frequency background noise which is inherent in certain commercial-records, usually as a result of granular structure of the record material, it often is preferable in playing such records to cut off all frequencies above some deter- V I fully reproducing the middle register and the desirable bass frequencies.

I have discovered, as another aspect of this invention, that if the stylus is only lightly gripped at its upper end by the rubber member.

in which it is anchored it will gointo rotational vibration about a center at or near the point where it contacts the coil-support, when actuated at and above some critical frequency and will thereupon fail to transmit efficiently to the coil-support all frequencies above said critical frequency. This means that the stylus will function as a low-pass mechanical filter or cut-off device if it is only lightly grippeds at its upper end by the soft rubber in which it is embedded. Tightening the grip of the rubber on the stylus raises the frequency at which cut-off occurs.

" Thus, by squeezing the rubber around the stylus or by selecting a less resilient rubber compound, or both, the cut-off frequency can be raised to any desired extent. Hence, if it is purposed to dusted, as occasion demands, to give the most satisfactory reproduction which the'quality of the record being played will permit.

A practical embodiment of the invention will I now be described with reference to the accompanying drawing, wherein:

Fig. 1 is a longitudinalsectional view, on a greatly enlarged scale, of a moving-coil pick-up incorporating the invention;

j Fig. 2 is a view looking upwardly from below Fig. '1; and

Fig. 3 is a fragmentary sectional view taken along the line 3-3 of Fig. 1. y

provide a pick-up which is most satisfactory for I playing commercial records afflicted with back ground noise, the stylus-supporting rubber member would be arranged to grip the stylus rather lightly and thus establish a cut-off point low enough to exclude most of the noise, but without too badly detracting from the tone quality. Conversely, if it is desired to providea pick-upcapable of faithfully reproducing frequencies up to a relatively high level, the rubber member would be arranged. to grip the stylus more tightly.

Observance of the above-described phenomenon and recognition of .the desirability of bein able to. play records of various qualities, each to the best possible advantage, has prompted ,me

. It is to be borne in mind that all three views are greatly magnified and that thepick-up device illustrated is in reality very small-the diameter of the moving coil being of the order of three-eighths inch while other dimensions are generally proportional.

Usually the field structure employed includes a permanent magnet together with suitable polepiecesand other components; but the invention here under consideration does not entail any departure from prior practice as respects field structure design and for that reason I have indicated only such fragments of the field structure as are immediately adjacent the elements with which the invention has especially to do.

The field pole-pieces are .indicated in Fig. 2 by reference numerals I and 2 respectively; and a core member 3 of magnetic material constitutes a passive part of the field structure and is situated midway between the pole-piece faces. Said core member provides a low reluctance path for the magnetic lines of force while at the same time serving as a support for elements presently to be described. It will be observed that core member 8 is circular in form, as viewed in Fig. 2, and that its upper end portion is of reduced diameter (see Fig. *1) and is pressed into a part 6 which supports the coremember in fixed relation to the aforementioned pole-pieces.

Between each pole face and core member 3 is a narrow magnetic gap in which is disposed the of-turns of fine copper or aluminum wire wound on the cylindrical and tubular base portion 6a of a cup-like thin metal coil-support 6, which preferably is cone-shaped below; the cylindrical base portion and somewhat truncated at the apex -portion 6b, as clearly illustrated in Fig. 1.

Coil-support 5 should be of low mass yet adequately rigid to transmit with minimum loss even to conceive of means whereby the gripping action of the rubber on the stylus can quickly and easily be adjusted so as to raise and lower, at will, the

cut-off level. What I consider to be the most convenient, operationally, and at the same time one of the most easily produced instrumentalities for carrying this idea into effect is a device in the nature of a 'collet chuck "which serves as a holder for the rubber-member and grips the same with a tenacity which is variable in response to rotation of an adjusting nut.

From the foregoing .it may rightly be conchided that a second object of this invention is to provide a pick-up construction which can be adapted to cut off at anydesired frequency level whereby to facilitate suppression of background noise; and that a third object is to devise means through which the cut-off level can be raised and lowered at will, so'that the pick-up can be adthe highest desirable frequencies from the stylus tothe moving coil. Preferably it is formed from thin sheet aluminum, and to further reduce its mass without undue loss ofrlgidity it may be perforated with small hoes as depicted irrFig. 2.

- The pick-up is designed for use only with lateral-cut recordings and, accordingly, is pivotally supported torotate about an axis correspending approximately to line I in Figs. 1 and 2.

'I'he plane of oscillation of the coil support and represented in Fig. 2 by coil is indicated by arrows 8 and 9 in' Fig. 2, and said plane is radial to the arc of the record groove line Ill. The direction of rotation of the record is indicated by arrow heads on line l0.

The means employed for pivotally' mounting the coil-support is not of the essence of the present invention, but it is advantageous and economical to makeuse of a pair of elongated rectangular soft rubber blocks II and I! which are seate in diametrically opposite slots formed in core member 3, and whichrubber blocks bear axial direction.

against opposite interior surface areas of the coil support, as clearly shown in Fig. 1. These soft rubber pivotal supports constitute subject matter of my above-mentioned co-pending application, and their use is particularly desirable here because they makeit easy to withdraw the moving coil and coil-support from the pick-up in event it becomes necessary to make a replacement.

said angle a be neither too small nor too large. If said angle is too small the radial pressure between the stylus and contacting surfaces of the aperture may be great enough to cause the coilsupport to follow lengthwise oscillations of thestylus as a consequence of frictional drag; and

if said angle is too large there is apt to result an The pin or rod l3 and the pointed sapphire or i needle-point l4 embedded in its lower end are here denominated, collectively, as the stylus. The sapphire or needle-point is, of course, intended to engage the record groove and the stylus is oscillated laterally by theundulations of said groove in the plane indicated by arrows 8 and 9. The upper end of the stylus is embedded in a bushing-like member I 5 of resilient material such as soft rubber, which normally functions as a pivotal center or fulcrum about which the stylus oscillates when actuated by the record groove undulations. Member l5 also allows the stylus to move freely-lengthwise of itself, to a limited extent, relatively to the other parts of the pickup, and it further functions as a damping means for preventing free vibration of the stylus, besides operating as a cushion to absorb the force of the blow in event the pick-up is accidentally dropped on the record.

It. is essential to good operation of the pick-up that lateral oscillations of the stylus which are imparted thereto by the lateral 'record undulations be transmittedfaithfully and with substantially full magnitude to coil-support 6 and thence to movingcoil 5, whereby to cause oscillatory rotation of coil 5 about axis 1 in accurate conformity with the record groove undulations corresponding to the recorded sound. But it is greatly to be desired that lengthwise vibration of the stylus be not transmitted to coil-support 6 because such vibrationof the coil-Support would give rise to what has hereinbefore been described into a well or recess, as shown in Fig. 1, for the reception of a small horn fiber disk II, which is cemented in place and apertured as shown. The aperture I 8 in the sheet metal is large enough to clear the stylus so that the latter bears only on the fiber surface. Fiber happens to be a good bearing material for this purpose, but any other ,suitable material could be substituted. 25

I have observed thatif the material constituting the bushing-like member I5 is quite yieldable and is compressed only lightly around the upper end of the stylus,the latter will oscillate about its upper end as a. fulcrum throughout as frequency band comprising the lower and middle register and frequenciesup to say four or live kilocycles. At some frequency of the order of four or five kilocycles, or thereabout, the center of vibration of the stylus will abruptly shift from, t the upper end thereof to the region'immediately f adjacent disk i1; and this. of course, means that the stylus is no longer highly eflective as a me- 40 quencies above thepoint wher the above-men- I as needle-talk; and since the surface-area of the coil-support is necessarily considerable the audible disturbance would be quite pronounced if such transmission were not prevented or at least greatly restricted. Substantial affords a close running fit for the stylus-thus permitting the stylus to oscillate lengthwise in-' dependently of and relatively tothe coil-support avoidance of needle-talk is here achieved by providing an aperture in the apex of the coil-support which' while eliminating or substantially restricting lat era'l lost motion between stylus and coil-support. This desirable result can be accomplished with a simple aperture of circular or otherionfiguration gauged to slidably fit the stylus; but it is difficult to achieve and maintain, with a circular aperture, a close sliding fit and at the same time prevent the coil-support sticking to the stylus and being resultantly vibrated with the stylus in the As a result of considerable thought and experimentation I have found a wholly practical solution of the aforementioned difiicultyfand this consists in the provision of an apex aperture i6 (see especially Fig. 2) so formed as to present to the stylus a V-slot having an acute angle a so oriented with respect to the record groove that the traction of the record pulls the stylus forvvlardly into said slot. This ensures that the stylus will always bear against the two sides of the V-slot so that there can be no lateral lost motion between stylus and coil-support as the stylus oscillates laterally in response to the record groove undulations; but it is necessary that the dium for transmitting the record undulations .to the coil-support and that, consequently, the fretioned shift occurs are largely or completely suppressed. By using a less yieldable material for,

member i 5 or by increasing the compressive force thereon, or both, the frequency at which suppression or cut-oil occurs may beraised. It is thus possible to vary the cut oif level by several kilocycles-which renders it practicable to specifically design the pick-up for playing to best advantage either low grade or high grade records .or to establish the cut-oil point at a level which representsacompromise between the two.

So far nothing has been said, in this detailed description concerning the provision for varying at will the cut-ofl' point; and that omission is deliberate in that I wish to emphasize that the feature under discussion is not basically dependent upon the inclusion ofadjusting means which permit the user to alter the point of cut-oil from time to time as he may see fit.

. It may not be feasible to market indiscriminately a pick-up which is capable of being incorrectly adjusted with respect to the particular record to be played and for that reason sales to the general public of pick-ups constructed in accordance with this invention may be largely confined to such as are fixedly adjusted at the outset to cut off at such a level as will produce the best results with ordinary records. But as concerns the class or trade 'capableo'f appreciating the necessity of making appropriate adjuste ments in harmony with the quality of the record in hand, it is practicable to supply pick-ups having the feature of adjustability depicted in Figs.

1 and 3 and presently to be described.

Instead of simply inserting rubber bushing II into a recess drilled in core member 3 and fixedly determining at the outset the tenacity with which said bushing grips the stylus, the bushing may be mounted in a collet l9 which is split at three or more points 20, as shown in Fig. 3, and provided with an arbor 2| threaded at its upper end and engaged by a knurled adjusting nut 22. The

- collet bears at 23 against a tapered internal surface in recess 24 which causes the collet to contract and increase its grip upon bushing l when nut 22 is turned in the direction which will cause an upward movement of. arbor 2|.

Opposite rotation of nut 22 will cause the compressive force on bushing l5 to be diminished. Thus, the user is enabled to adjust the pick-up to best advantage for any record which he maybe about to play. It will be apparent that the feature 'just described constitutes a mechanical low-pass wave filter whereof the point of cut-off may be adjustable by the user or, alternatively, may be determined and fixed at the factory. Since the stylus is only frictionally secured to bushing 'it can WheneVer'necessary, easily be withdrawn for replacement; and this does. not necessitate removal of the coil-support.

I claim:

1. The combination in a phonograph pick-up for playing lateral-cut recordings, of a moving coil pivotally mounted for rotary oscillation in a magnetic field about an axis of rotation extending transversely of the coil, an elongate stylus adapted at one end to engage a record groove, a resilient anchorage for the other end of said stylus, which anchorage is operative as a fulcrum about which said stylus is rotatable in response to actuation by the record groove undulations,

said anchorage being yieldable to permit lengthwise oscillatory movement of said stylus to a lim-- ited extent, and structure intercoupling said coil -with said stylus for translating lateral oscillations of the stylus intocorresponding rotational oscillations of the coil about said axis, said stylus being movable lengthwise substantially without imparting motion to said structure.

2. The combination in a phonograph pick-up for playing lateral-cut recordings, or a pivotally mounted coil-support, a moving coil wound on said support and rotatable therewith, and a stylus for actuating said coil-support in response torecord groove lateral undulations, said stylusbeing so coupled to said coil-support that lateral oscillations of the stylus are transmitted efilciently through the coil-support to said movin coil in a manner effective to oscillate said coil in harmony with the lateral record groove undu-. lations,. said stylus. being movable lengthwise independently of said coil-support and therefore yieldable to pinch-efiect without actuating said coil-support; v

3. The combination in a phonograph pick-up for playing lateral-cut recordings of a cup-like .coil-support, liaving a base portion and anapex portion axially spaced from said base portion, a moving coil wound on said base portion, said coil-support being pivotally mounted and having an axis of rotational oscillation extending diametrically of said coil and through said base portion, the apex portion of said coil-support having an aperture, a stylus extending from the interior of said coil-support through said aperture to the exterior of said support and adapted to engage a record groove at its exterior end, the

- other end of said stylus being resiliently an-' chored so that it is relatively free to move lengthwise to a limited extent, said stylus having a sliding fit in said aperture.

4. The combination in -aphonograph pick-up for playing lateral-cut recordings, of a cup-like coil-support having a main axis, said coil-support including a base portion concentric with said main axis and an apex portion concentric with said main axis and spaced from said base portion along said main axis, said coil-support having an axis of rotational oscillation extending through said base portion perpendicularly-to said main axis, a moving coil wound on said base -portion, an elongate stylus having a longi tudinal axis coincident with said main axis, said stylus extending through and slidably fitting an aperture in said apex portion, one end of said stylus being adapted to engage a record groove,

and resilient means for anchoring the other end of said stylus, said resilient means being operative as a fulcrum about which said stylus oscillates when actuated by a lateral-cut record groove, said resilient, means being "yieldable to permit said stylus freely to vibrate lengthwise to a limited extent. I

5. The combination in a phonograph pick-up for playing lateral-cutrecordings, of a, coil-support having a main axis, a' moving coil wound on said coil-support concentrically with said main axis, said coil-support having an aperture through which said main axis extends, the configuration of said aperture, as viewed when looking endwise at said axis, including a V-slot, an

elongate stylus having its longitudinal axis approximately coincident with said main axis and extending through said aperture, one end of said stylus being exterior of .said coil-support and adapted to engage a record groove, and means forming a resilient anchorage for the other end of said stylus, said V-slot beingso oriented that the stylus is forced forwardly into it by the traction of the moving record groove onthe stylus,

said V-slot being effective to preclude lost motion between said stylus and coil support'with respect to lateral oscillatory motion imparted to I the stylus by the lateral record groove undulations, said stylus being freely slidable lengthwise through said aperture, said coil-support, together with said coil, being mounted for rotational oscillation about an axis extending diametrically of said coil.

76'. The combination in a phonograph pick-up for playing lateral-cut recordings, of a moving coil pivotally mounted for' rotary oscillation in a magnetic field about an axis of rotation extending transversely of the cell, an elongate stylus adapted at one end to engage arecord groove, a resilient anchorage for the other end of said stylus, which anchorage is operative as a fulcrum about which said stylus is rotatable in response to actuation by the record groove lateral undulations, said anchorage being yieldable to adapted at one end to engage arecord groove, a resilient anchorage for the other end of said stylus, which ancorage is operative as a fulcrum about which said stylus is rotatable in response to actuation by the record groove lateral undulations, said anchorage being yieldable to permit lengthwise oscillatory movement of said stylus to a limited extent, and structure for translating lateral oscillations of the stylus into corresponding rotational oscillations of the coil, said structure having an apertureforming a bear-ing in which said stylus is a close sliding fit and which constitutes the medium coupling the stylus to the structure for efiectuating the aforementioned translation, the configuration .of said aperture,

- as viewed when looking from one end of said stylus, being non-circular'and including a V-slot oriented to receive said stylus, the latter being movable forwardly into the V-slot by the traction A of the'moving record.

8. The combination in a phonograph pick-up for playing lateral-cut recordings, of a cup-like coil-support having a main axis, said coil-support having a tubular base portion concentric with said main axis and an apex portion spaced from said. base portion lengthwise of said main axis, said coil-support including a conical por- ,tion interconnectin said base portion and apex portion, a magnetic core member disposed within said base portion, pivot means suspending said coil-support from said core member and ar ranged to permit rotary oscillation of said coilsupport about an axis extending transversely of said main axis and through said base portion, a moving coil wound on said base portion, a rubber-like member carried by said core member within said coil-support, and an elongate stylus having its longitudinal axis coincident with saidmain axis, one end of said stylus being anchored in said rubber-like member, said stylus extendingthrough an aperture in said apexportion to the exterior of said coil-support and adapted at its exterior end-to engage a record groove, said stylus being closely fitted to said aperture to avoid lateral lost'motion between the stylus and the coil-support, said stylus being freely slidable lengthwise through said aperture.

9. The combination in a phonographpick-up for playing lateral-cut recordings, of a cylindrical magnetic core membe'rhaving a main axis, a cuplike coil-support having a base portion encircling said core member and concentric with saidm'ain axis, resilient means pivotally connecting said coi1-support-to said core member and permitting said coil-support to oscillate rotationally about an axis extendingdiametrically through said base portion and perpendicularly to said main axis,

said coil-support having an apex portion concentric with said main axis and spaced from said base portion, a non-metallic member carried by said coil-support at said apex portion and having an aperture, the configuration of said aperture, as viewed when looking'endwise at said main axis, being non-circular and including a v-slot portion, a resilient rubber-like insertcarried by said core member, and an elongate stylus having its longitudinal axis substantially coincident with said main axis, one end of said stylus being anchored in said insert, said stylus extending through said i stylus is free to oscillate longitudinally independently of said coil-support while at the same time lateral lost motion between the' stylus and coilsupport is obviated.

10. The combination in a phonograph pick-up for playing lateral-cut recordingsof an elongate stylus, a resilient rubber-like member embracing one end of said stylus and constitutingan anchorage therefor, adjustable means for variably cornpressing said rubber-like member for altering its grip on said stylus, a moving coil, and structure fortransmitting lateral oscillatory movements of said stylus tosaid moving coil, said stylus being movable lengthwise independently of-said structure. i

ll. The combination in a phonograph pick-up for playing lateral-out recordings, of an elongate stylus, a resilient rubber-like member embracing one end of said stylus and constituting an anchorage therefor, a contractible-expansible collet em bracing said rubber-like member, manually operfor playing lateral-cut recordings, of a core member having a main axis, acup-like coil-support concentric with said main axis and having a base portion encircling said core member, said coilsupport having an apex portion concentric with said main axis and spaced from said base portion along said main axis, said core member having an axial bore terminating in a recess at theend within said coil-support, a collet chuck seated in said recess and having. an arbor passing through said bore, means for moving said arbor lengthwise,

for actuating said chuck, a resilient rubber-like member gripped by said chuck,.and an elongate stylus embedded at one end in said rubber-like member and extending through an aperture in said apex to the exterior of said coil-support, the other end of saidstylu's being adapted to engage a record groove, said stylus slidably fitting said aperture and freely movable therein lengthwise, said coil-support being pivoted for rotary oscillation about an axis perpendicular to said main axis and remote from said apex.

13. The combination in a phonograph pick-up for playing lateral-cut recordings, of a-coil-sup-" port having a main axis, said coil-support including abase portion and an apex portion spaced from said base portion along said main axis, a movingcoll wound on saidbase portion concen-,

trically with said main axis, said coil-support an elongate stylus having a longitudinal axis 'substantially coincident with said main axis, said aperture and adapted at its other end to engage J a record groove, said v-slot portion being so oriented that the-traction oi the record forces said stylus into said v-slot portion, the angularity of said V-slot portion being so chosen that said stylus extending through said apex portion and drivingly coupled thereat to said coil-support, the exterior end of said stylus being adapted to engage a record groove, and arubber-like member forming a pivotal anchorage for the other end of I said stylus'and in gripping engagement therewith.

14. The combination in a phonograph pick -up for playing lateral-cut recordings, of a coil-sup- Dort having a main axis, said coil-support including a base portion and an apex portion spaced from saidbase portion along said main axis, a. moving coil wound on said baseportion concenbeing plvotally mounted and having an axis of rotational oscillation extending diametrically of said coil and perpendicularly of said main axis, an elongate stylus having a longitudinal axis substantially coincident with said main axis, said stylus extending through said apex portion and drivingly coupled thereat to said coil-support, the exterior end of said stylus being adapted to engage a record groove,- a rubber-like member forming a pivotal anchorage for the other end of said stylus, and adjustable means for variably gripping said rubber-like member for altering its grip on said stylus. I

15. Theeombinatlon in aphonograph pick-up for playing lateral-cut recordings, of an elongate stylus, a resilient rubber-like member embracin 2,886,089 trically withsaid main axis, said coil-support one end of said stylus and constituting an anchorage therefor, a. contractible-expansible collet embracing said rubber-like member, a moving coil, and structure for transmitting lateral oscillatory movements of said stylus to said moving coil, said structure being connected to said stylus at a point remote from said anchorage.

16. In a moving-coil type phonograph pick-up for playing lateral-cut recordings, a coil arranged for, oscillatory movement, a stylus adapted to engage a record, means supporting said stylus for vboth longitudinal and lateral movements, and

means for effecting oscillatory movement of said coil in response to lateral movement of the stylus whilefpermitting longitudinal movement of the stylus substantially independently of said 0011.

g LLOYD J. BOBB. 

